This invention relates to a method and device for removing undesirable gases from well water and more particularly to a device and method for removing hydrogen sulfide from well water which incorporates an adsorbent material which may be regenerated in situ.
Well water contains a variety of dissolved gases which tend to give the water a strange taste or odor. Among the main contributors to the strange odor or taste in well water is hydrogen sulfide. Such water is commonly referred to as "sulfur water". The severity of the odor or taste of the water is a function of the concentration of the dissolved gases within the water. Thus, it is apparent that by reducing the concentration of dissolved gases within well water, the severity of the unpleasant taste or odor of the water may be reduced. It is well known that by passing well water through an activated carbon or charcoal filter, that the concentration of undesirable gases and in particular, hydrogen sulfide, may be lowered. One drawback to this method is that the adsorbant ability of the activated carbon or charcoal which is repeatedly exposed to well water is reduced over a period of time. Thus, after a period of time an activated carbon or charcoal filter is no longer able to reduce the concentration of hydrogen sulfide in well water by a sufficient amount to eliminate undesirable tastes or odors from the water. Once this point is reached, it is necessary to either replace the activated carbon or charcoal, or restore its ability to adsorb hydrogen sulfide, i.e. regenerate the activated carbon or charcoal. It has been known for some time that the adsorbent ability of activated carbon or charcoal which has been exposed to hydrogen sulfide may be regenerated by exposing the activated carbon or charcoal to steam at high temperatures.
Various methods and devices for the removal of hydrogen sulfide from water or the regeneration of adsorbent materials are disclosed by the following group of patent references. Each reference pertains in one way or another, to removing hydrogen sulfide from water or the regeneration of adsorbent materials.
______________________________________ U.S. Pat. No. Patentee ______________________________________ 1,898,688 Rose 2,181,672 Sutcliffe et al. 3,192,156 Joyce 4,045,553 Mitsumori et al. ______________________________________
Sutcliffe et. al. (U.S. Pat. No. 2,181,672) discloses an adsorbent filter. Sutcliffe discloses a cylinder containing activated carbon connected to a steam pipe for flushing the carbon after it has become partially or completely charged with a solvent or substance to be recovered. Sutcliffe does not disclose use of activated carbon to remove hydrogen sulfide from well water or the regeneration of the carbon by raising water in the vicinity of the carbon to the boiling point so as to restore the adsorption capabilities of the carbonaceous material.
Rose (U.S. Pat. No. 1,898,688) discloses a method for the purification of battery acid. Rose passes battery acid through activated carbon until the discharge of the battery acid from the activated carbon is no longer of satisfactory purity, at which time the supply of battery acid is stopped and steam is forced through the activated carbon and out the waste pipe so as to drive off the acid previously adsorbed by the carbon. Rose does not disclose the use of activated carbon as a means of removing hydrogen sulfide from well water nor the regeneration of the carbonaceous material in situ by bringing liquid in the vicinity of the material to the boiling point.
Joyce (U.S. Pat. No. 3,192,156) discloses a method for the removal of hydrogen sulfide from water. Joyce passes hydrogen sulfide containing water through a bed of activated carbon impregnated with manganese dioxide to remove the hydrogen sulfide and then through a cationic exchange water softener to remove water soluble manganese and iron compounds. Joyce requires that the activated carbon be impregnated with manganese dioxide in order to attain outstanding hydrogen sulfide removal. Nowhere does Joyce disclose a device or method for regeneration in situ of the activated carbon nor the bringing of water in the vicinity of the activated carbon to the boiling point so as to restore the hydrogen sulfide adsorption capabilities of the activated carbon.
Mitsumori et al. (U.S. Pat. No. 4,045,533) discloses a method of treating silver impregnated activated carbon. Mitsumori restores the spent silver impregnated activated carbon with steam. Mitsumori does not teach or suggest the use of activated carbon for the removal of hydrogen sulfide from water, nor does Mitsumori suggest the attachment of a device to a source of well water. Nowhere does Misumori teach or suggest the regeneration of activated carbon or charcoal by the heating of water in the presence of impregnated activated carbon or charcoal so as to produce steam, and thereby regenerate the activated carbon or charcoal.
None of these prior art references are suitable for use in a home environment to regenerably remove hydrogen sulfide from well water.